Blackmail (1929)

Continuity mistake: When the artist speaks to his landlady, his walking cane is tucked horizontally under his arm. In the very next shot, however, the cane jumps to a vertical position and is now in his hand. (00:21:00)

Jean G

Tracy: Look, here, Miss, you tell him! Tell him that he's playing with fire. And we shall all of us burn our fingers.

Trivia: Hitchcock's cameo is towards the beginning on the train. The little boy is playing with his hat.

manthabeat